A method is presented for position and displacement measurements of the six degrees of freedom by use of a patterned surface element observed by a static interferometric vision system. The surface element is made of a regular pattern of circular holes etched on a chromium layer deposited onto a flat glass plate. The in-plane coordinates (x, y, θ_(z)) are reconstructed with a subpixel resolution by a vision method based on phase measurements. The out-of-plane coordinates (z, θ_(x), θ_(y)) are reconstructed by phase-shifting interferometry. Resolutions achieved by the proposed method are in the range of microradians for the measurement of angles and of nanometers for the position and displacement.
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